This is a prospective, multicenter, open-label, phase Ib/II clinical study to evaluate the safety and efficacy of EZH2 inhibitor Zeprumetostat in combination therapy for patients with relapsed or refractory mature T-cell and NK-cell lymphomas.

Inclusion Criteria:

• Voluntarily participate in the clinical study; fully understand and be informed about the study and sign the Informed Consent Form (ICF); willing to comply with and capable of completing all trial procedures;
• Age ≥ 18 years
• Pathologically confirmed mature T-cell and NK-cell lymphomas.
• Using the Lugano 2014 criteria, the patient must have at least one measurable or evaluable lesion
• Participants must have experienced disease progression, treatment failure, or intolerance following standard therapy. Patients with ALCL are required to have previously received anti-CD30-targeted therapy, while patients with NKTCL must have previously been treated with pegaspargase or L-asparaginase.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
• Adequate organ and bone marrow function

Exclusion Criteria:

• Lymphoma involvement in the central nervous system or meninges
• Active infections
• Prior treatment with an EZH2 inhibitor or an EZH1/2 dual inhibitor that was discontinued due to intolerance to toxicity;
• For patients enrolled in Cohort 1, prior treatment with a JAK inhibitor that was discontinued due to intolerance to toxicity;
• For patients enrolled in Cohort 2, prior treatment with an HDAC inhibitor that was discontinued due to intolerance to toxicity.
• History of Human Immunodeficiency Virus (HIV) infection and/or Acquired Immunodeficiency Syndrome (AIDS).
• Patients with mental disorders or those unable to provide informed consent
• Any other condition deemed by the investigator to be unsuitable for study enrollment;
• Pregnant or breastfeeding women, and subjects of childbearing potential who are unwilling to use contraception;
• Individuals with a known hypersensitivity to any of the investigational drugs.